How Much Electricity Do Your Gadgets Really Use?

Are they electricity vampires or sippers? Here's what's worth worrying about and what's not. 

We all get anxious when the battery levels on our phones and laptops and iPads get low. Dead batteries can lead to depression and withdrawal symptoms. The longest seconds are those that pass between the time I plug in my iPhone charger and when the white Apple icon finally appears on the screen as the device starts to boot up.

Do you get sheepish about "borrowing" electricity from random people in random places to recharge your phones or laptop? Do you worry about how much electricity you're freeloading?

You shouldn't.

Pop quiz: how much electricity (to the closest 10 kilowatt-hour) does it take to power your iPhone or Android for a year? 1 kWh? 10 kWh? Or 100 kwh? The answer: 1 kWh.

This is the amount of electricity you'd need to power ten 100-watt incandescent lightbulbs for an hour. Far from anything worth being sheepish over, 1 kwh costs about 12 cents.

To be specific, your iPhone battery holds a charge of 1,440 mAh, or about 5.45 watt hours. If you fully drained and recharged your phone everyday, then over the course of a year you would have to feed it about 2,000 watt hours, or 2kWh. At an average price of 12 cents that means that your phone uses about one quarter's worth of electricity per year. As for your iPad, keeping it fed costs just $1.36 a year, according to the Electric Power Research Institute. Your average laptop, with its far bigger screen, uses about 72 kWh, costing some $8 a year.

That's right, you can run your phone, iPad and laptop for a whole year for about $10 -- less than the cost of three gallons of gasoline.

So don't worry about plugging in that charger and bumming a little juice. Don't worry about the ongoing carbon footprint of your electronics devices. Ignore the worryworts who try to make the case that your phone uses the electricity of two refrigerators if you add up all the processing power going on in the cloud. That's been thoroughly disproven.

Instead, if you want to reduce your electricity (and overall energy) use, better to think holistically about the entire scope and scale of your energy diet rather than the tiny loads being sipped by your favorite toys.

As Michael Bluejay (who goes by the nickname Mr. Electricity) says: "Obsessing about whether it's better to boil a cup of water on an electric burner or in a microwave, or whether you wear out your lights quicker by turning them off rathr than keeping them on, is a waste of time and misses the point. Such trivia won't make a dime's worth of difference in your electric bill. It's the bigger things that matter."

The good news is that the big energy suckers in the your home -- air conditioner, refrigerator, clothes washer, and even lightbulbs -- have become far more efficient. Compared with 1980 models, clothes washers now use 70% less electricity. New LED lightbulbs use 80% less. Refrigerators use 60% less.

Even gaming systems have seen dramatic improvements. Early iterations of Sony 's Playstation and Microsoft 's Xbox drew 150 watts when in play mode. Now they're down to less than 100 watts -- costing about $40 a year, depending on how much you play. That's about as much as a big-screen plasma TV at $42. Your cable box with DVR averages about 230 kWh per year, for about $28.

Full List: How Much Power Your Devices And Appliances Use

In cutting your energy usage, sometimes it makes sense to upgrade appliances. But sometimes it makes more sense to change your behavior.

Take water heating, for example.

Making water hot accounts for 18% of the average home's energy bill, according to the EPA, or about $600 a year. Tankless water heaters will save you $10 or more in electric costs per month. Solar water heating systems can nearly eliminate your water heating costs altogether. But unless you're building a new house or your old water heater has died, a new system doesn't make sense because it could take 10 years or more worth of savings to recover the high installation cost. Instead, says Mr. Electricity, simply wash your clothes in cold water instead of hot or even warm. That will save you $150 a year in the average home, and will make your clothes last longer.

The economics are a little better on clothes washers. Getting the dirt out of your togs uses as much as $100 worth of power a year with newer front-loading machines. An old top-loading clothes washer uses twice as much juice. With those economics you can buy a new washer and within five years you'll make back the upfront investment in energy savings.

Drying your clothes costs about 50 cents per load -- about $200 a year for most families. If laundry racks don't appeal, try putting a dry towel in there with your wet clothes. The towel will soak up a lot of water from the clothes; take it out halfway through the cycle and hang it up to air dry.

Lighting. This is, for many homes, the best way to save electricity. Traditional incandescent bulbs are more heaters than they are light sources -- 90% of the electricity they take in comes out as heat, not light. A single 60 watt incandescent lightbulb, on for 10 hours a day, will use 220 kWh per year, costing about $26 (assuming 12 cents per kWh). A compact fluorescent can put out the same light for just $7 per year. And a newer LED bulb can do it for $4.40. I'm a fan of the new LED bulbs made by Cree, (which I wrote about for Forbes here). They might cost $10 a bulb, but you'll make that back with just a few months of energy savings. And vitally, for those of us who can't stand the flickering of CFLs bulbs, the Cree LEDs don't flicker and their warm white variety is nearly indistinguishable from an incandescent. Unlike incandescents, LED bulbs never burn out, and because they put out very little heat you'll save on your air conditioning.

Think about it: if you were to replace 10 incandescent bulbs around your house with 10 LED bulbs you could save more than $210 a year (assuming they're on 10 hours a day). That's enough to pay back your LED investment in less than a year and have enough left over to power all your electronic devices, TV and Xbox. Sweet.

And then there's the automobile. This is the real energy guzzler for most of us. Assuming that you drive 15,000 miles and get a respectable 25 miles per gallon you'll be buying 600 gallons of gasoline a year. At an average $3.60 per gallon nationwide, that will cost you nearly $2,200 a year. That's about 15 cents per mile, or enough energy expense to power 270 laptop computers.

So at what point does it make sense to buy an electric car, like the Tesla? It takes about 85 kWh of electricity to fill up a Model S Tesla with a 300-mile-range battery. This amounts to about $10 worth of electricity, for an average cost per mile of about 3 cents. If you're driving that same 15,000 miles a year in your Tesla your fuel bill will thus come to about $450. That's a hefty $1,750 savings over gasoline, but then again, the Tesla does cost at least $60,000, and that fuel savings will be wiped away when you have to shell out $12,000 to replace your battery after five years or so.

For the same $60,000 you could buy a brand-new Audi A4 for $35,000, have $25,000 left over to buy 10 years worth of gasoline, and never have that anxiety that your batteries might run out of juice before you get to your destination.

Full List: How Much Power Your Devices And Appliances Use